Which of the following is not a part of human central neural system?

Question

Accepted Answer

A. 1. First, recall what the **central neural system (CNS)** consists of.
The CNS is made up of the **brain** and the **spinal cord**, and both are covered by three protective membranes called **meninges**.

2. Identify the three meninges by name.
Given that meninges protect the CNS, the layers from outside to inside are:
$$
	ext{Dura mater} 	o 	ext{Arachnoid} 	o 	ext{Pia mater}
$$
Therefore, all three of these belong to the CNS.

3. Now check the odd one out — **Pericardium**.
The pericardium is a double-walled membranous sac, but it surrounds the **heart**, not the brain or spinal cord, so it has nothing to do with the nervous system.

Hence, the structure that is **not** part of the human central neural system is **Pericardium**, so the answer is **Option A**.